Until 1994, O. calypsus was considered simply a variety of O. heldreichii but since that time has been given full species status and maintains three named varieties, maxima, scolopaxoides and the taxon featured here, pseudoapulica.
This position has recently changed again with maxima (which was
always something of a "catch all" taxon) being redistributed into
other classifications, principally O. colossaea.
O. calypsus v pseudoapulica was (at the time of writing) still a recognized variety
having first received a formal description in
1995 by Delforge. Its distribution is primarily the Cyclades
and Rhodes which therefore brings it into contact with
both the type species and variety scolopaxoides.
Hybridization with these (and indeed other species) have created
many intermediate populations which serve to make firm
identification difficult in many areas.

The most important single feature that distinguishes pseudoapulica
is the way in which the lip margins initially recurve
tightly behind the main body of the lip and then reflex out and forward
so that they are visible (sometimes only narrowly) from a face on view.
In scolopaxoides there
is significant recurvature but no reflexation and
the lip margins simply form a tight pleat at the back of
the body. O. calypsus itself is similar to scolopaxoides but
the lip has a lower waistline and looks much less scolopaxoid. As mentioned
earlier however, finding pure populations can often be difficult and the
balance of probabilities often plays a significant part in identification.

The photos all come from Rhodes and picture 9 illustrates an
unusual hypochromatic hybrid with an unknown species from the sphegodes group.